Copy Rock Band DLC from SD back to Wii

I have my Wii set up with uLoader so that I use the nand emulation to store my DLC on my USB stick. I have tested it and DLC is properly saved to the USB and can be played.

My question is this: is there any way to get all my DLC which I have stored on my SD card back into the Wii memory (aka my USB stick with nand emulation)?

I haven't been able to find any solution so far and I've gone about starting to redownload everything again (which isn't so bad since I can skip the painfully long step of copying the content from nand to the SD card).

The Wii management options are oblivious to any DLC on the SD card since I assume Rock Band is set up in a way that only the game looks for it there.